1. Field
The described technology relates generally to a rechargeable battery having a member that can absorb vibration and an impact.
2. Description of the Related Art
A rechargeable battery can be discharged and recharged, unlike a primary battery that cannot be recharged. A low capacity rechargeable battery is often used for a small portable electronic device such as a mobile phone, a laptop computer, and a camcorder, and a large capacity rechargeable battery is often used as a power source for driving a motor such as for a hybrid vehicle.
Further a high power rechargeable battery module that uses a high energy density of non-aqueous electrolyte has been developed, and in such a high power rechargeable battery, a plurality of rechargeable batteries for driving a device requiring large electric power, for example, a motor such as an electric vehicle are coupled in series.
Further, a high power rechargeable battery module is formed with a plurality of rechargeable batteries that are generally coupled in series, and the rechargeable battery may be formed in a cylindrical shape and a quadrangular shape.
The quadrangular shape rechargeable battery includes an electrode assembly in which a positive electrode and a negative electrode are positioned with a separator disposed therebetween, a case having a space that houses the electrode assembly, a cap plate that closes and seals the case and having a terminal hole through which a terminal is inserted, and a terminal that is electrically connected to the electrode assembly and that is inserted into the terminal hole to protrude to the outside of the case.
The terminal is electrically connected to the electrode assembly through a lead tab, and the lead tabs are each fixed to the terminal and the electrode assembly. Due to an external vibration or impact, a contact between the lead tab and the electrode assembly and/or a contact between the lead tab and the terminal may become disrupted or ineffective.
Such a problem frequently occurs in a rechargeable battery that is applied to an object that continuously vibrates, such as an electric vehicle (EV) and a hybrid electric vehicle (HEV).
When a contact between the lead tab and the terminal or the electrode assembly becomes disrupted, an output of the rechargeable battery is deteriorated and much resistance heat occurs in a contact portion thereof. When much heat occurs within the case, an abnormal reaction such as decomposition of an electrolyte solution occurs within the case, and thus the rechargeable battery may explode or ignite.
Further, when the electrode assembly does not contact the case for insulation and is suspended to the lead tab, if an external vibration or impact occurs, all loads are concentrated to the terminal and thus the terminal may be deformed or cut.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.